Air conditioning is a well-known technology. In general, air is passed across the cooling coil (e.g., an evaporator) of a refrigeration circuit, where it is cooled and dehumidified to a certain extent.
In some known air conditionings systems, after flash-evaporating to a gas in the evaporator and absorbing heat from the air flowing across the evaporator as it does so, refrigerant in the refrigeration circuit—i.e., a particular type of operating air-conditioning coolant—is compressed to high pressure (and high temperature) in a compressor and then condensed back to its liquid phase in a condenser. A heat-removing cooling medium (e.g. air or, in some systems, water or other liquid medium) flows past the condenser to cool the refrigerant. Heat that the refrigerant has absorbed from the air flowing across the evaporator (as well as heat that has been imparted to the refrigerant due to compression, compressor motor cooling, and/or inadvertent absorption by the gas between evaporator and compressor suction) is transferred to the heat-removing cooling medium and “disposed” of, e.g., by venting the cooling medium to an outside environment, thereby allowing the refrigerant to continue cycling.
In other known air conditioning systems, which frequently are used, for example, in large commercial or multi-unit residential buildings, chilled water is used as the operating air-conditioning coolant instead of liquid/gas refrigerant. In such systems, an industrial chiller is provided (e.g., on the roof of the building) to chill water to temperatures on the order of 40° F. (A refrigeration system like that described above, which uses a gas/liquid refrigerant, compressor, and condenser, may be used within the chiller to chill the water coolant.) The chilled water circulates throughout the building through a system of conduits, which carry the chilled water to various circulatory branches throughout the building. For example, each branch could be an individual room, office suite, or residential apartment within the building. The chilled water flows through a cooling coil or evaporator within a fan-coil unit that is part of each circulatory branch, and air to be cooled (e.g., for human comfort or other cooling purposes) is blown across the cooling coil. The water, which has absorbed heat from the air blown across the cooling coil and become warmer, is cycled back to the chiller to be cooled once more.
On the other hand, atmospheric water-harvesting—that is, extracting moisture from the ambient atmosphere in sufficient quantities to provide for human/animal consumption and/or other, technical water and/or graywater-suitable purposes—is a somewhat less common endeavor than air conditioning, although there is, in fact, an established atmospheric water-harvesting industry. Although atmospheric water-harvesting uses a cooling process that is, conceptually speaking, generally the same as or similar to the cooling process used for air conditioning, the operational points in terms of how much the ambient air needs to be cooled and how much air needs to be processed are relatively different as compared to the corresponding operational points for general air conditioning. As a result, air conditioning systems and atmospheric water-harvesting systems have historically been viewed as separate, independent systems and have been developed as such.